Some three dimensional (3D) printers create objects layer by layer. These printers use additive manufacturing processes to build stacks of 2D slices into a 3D object from the based up. The dimensions and thickness of the 2D slices are precisely controlled through the movement of the printer head, i.e., extruder nozzle, and the build platform. This enables the printer to accurately control the shape and thickness of each layer printed. The thickness of the first layer applied to the build platform, however, is especially important because it affects the layer thickness as well as the adhesion of the object to the build platform. There is therefore a need for a system for precisely calibrating the distance between the extruder nozzle and build platform.